# Why is schizophrenia a thought disorder and bipolar a mood disorder?

Examining two major mental illnesses that are, loosely, grouped by mood and thought.

Schizophrenia is regarded as an illness associated with thought disorder.

Bipolar is regarded as a mood disorder.

Both conditions can lead to a psychotic break and behavioral disturbance. Hallucinations can occur in both.

Bipolar is characterized by depression with the occurrence of, at least, one episode of mania.

Schizophrenia is characterized by phases. An active phase, where psychotic symptoms peak and the negative phase, when the personality has little affect.

Given that both cause behavioral problems and changes to mood. That psychosis is based on false beliefs, and beliefs are thoughts. What is the scientific and the psychiatric basis for regarding schizophrenia as a thought disorder and bipolar a mood disorder?

-
Bipolar is regarded as a mood disorder. - Depends on whom you ask. What defines a mood disorder? What defines a thought disorder? What defines an illness? In all honesty, I don't think this is answerable given the current state of psychiatric science, but I'd be happy to be proven wrong... –  BenCole Aug 9 '13 at 16:56
To clarify, the difference would, semantically-speaking, be that one regards maladaptive thoughts while the other concerns maladaptive emotions. But where's the barrier between those two? Where's the barrier between those and physical/neurological 'illness'? French (and lots of European) psychiatry takes a psycho-behavior/lifestyle approach to addressing these issues, while in the US there's a much stronger pharmaceutical approach. –  BenCole Aug 9 '13 at 16:58